High levels of high density lipoprotein (HDL), also known as the "good cholesterol," are thought to protect against heart disease. However, what’s good for one disease may not be good for another. High levels of HDL have also been linked to increased breast cancer risks and to enhanced cancer aggressiveness in animal experiments. Now, a team of researchers led by Philippe Frank, Ph.D., a cancer biologist in the Department of Biochemistry and Molecular Biology at Thomas Jefferson University, has shown that an HDL receptor found on breast cancer cells may be responsible for this effect, proposing a new molecular target that could help treat the disease.